Marker lamp



March '17, 1931- J. P. JOHNS MARKER LAMP Filed April 27. 1929 INVENTOR.

TORN E Y.

March 17, 1931.

J. P. JOHNS MARKER LAMP Filed April 27. 1929 2 Sheets-Sheet 2 A TTORNE Y.

Patented Mar. 17, 1931 PATENT JOHN IE. JOHNS, OF NEW YORK, N. .Y.

MARKER LAMP Application filed April 27,

This invention relates to marker lamps of the type that are used as markers on the rear-end of trains and its objects are to provide a lamp as a marker that may be lighted by oil or electric current; more specifically, the invention relates to an adapter that may be applied to existing oil lamps so that they may be illuminated either by oil or by electricity.

Marker lamps of the type to which this invention applies are provided with four lenses giving indications in four directions and, for thesake of reliability, they must be usable asisolated units lighted by oil.

The oil tount has a capacity of about 50 hours and occupies a considerable portion of the base of the lamp. The flame is arranged to centre in the focal point of the lenses.

Most of the modern railway coaches are 1 equipped with electric lighting and when electric current is available, the marker lamps may be illuminated by an electric bulb which can be connected to a convenii-mt outlet. The electric. illumination oi" marker lamps has a niunber of advantages over the oil system. The source of illumination can be centered more accurately in the focus oi. the lenses, a stronger and more pronounced li ht beam is obtained and greater convenib i C') once obtains with its use.

In case the electric supply should fail, safety demands that an oil light be available and the present practice to use an oil marker light and a separate electric marker lamp. Those lights are removed a t the end of the journey and the labor of rcmoving and replacing them is doubled when separate oil and marker lamps are used.

It is the purpose of this invention to adapt existing oil burning lamps to use an electric bulb when an electric supply is available, but to be instantly convertible for use with oil when the electric supply fails. This result is obtained by an adapter secured within the lamp housing as a permanent fixture, but out of the way of the flame when the oil burner is in use, even when the housing is tilted from the vertical. To change over from oil to electric lighting, the

1929. Serial No. 358,710.

oil burneris removed from the .lountalul an electric bulb is screwed into the adapter, the lamp havingbeen previously plugged into the lighting mains of the car. By reversing this process and removing the bulb and replacing the burner, the lamp is ready for use with oil.

Owing to the lens apertures in the walls of the lamp housing, the adapter has to be specially formed to fit between a pair o'l apertures so as not to obscure the light or cast a shadow in the indication from any of the lenses. Also, it is necessary topro- 'vide a certain amount of adjustment in the location of the socket so as to bring the lamp bulb filament into the approximate focus of the lenses.

In the drawings, a standard.marker lamp is illustrated in elevation in Fig. 1,with the door open; a plan view of this lamp with the cover removed and with an electric bulb in place is shown in Fig. 2; Fig. 3 show; the relation of theadaptcr tothc lens apertures of thehousing; Fig. 4 is a detail, partly sectioned, showing the method of attaching the adapter to the housing; and, Fig. 5 is another detail, partly sectioned, showing the attachment of the adapter to the housing. i L

The marker lamp housing is indicated by 11, the base by 12 and the cover by 13. The

indications are given by the lenses 14, 1:), 16 and 17 located at right angles to each other as shown and having a ctnnmon to -al point at m in the centre of thehousing. The door 18 engages the vertical guides at 19 whereby the door may boslid open or shut.

The oil fount 20 1' on the base 12 and is held in position by the cleats ill but may he .slid out of the housing for trimming purposes. The oil burner at is of the usual type and terminates in the flame 23 at the focal point a.

The adapter 25 may be made from moulded material and is secured to the hous-" ing by means hereinafter referred to. The socket 25 is formed integral with 25 and centres on the axial line of the lenses a-b and is disposed with its centre pointing towards the focal point a. Terminals 27 may be provided in by which the electrical connections are made to the socket from the lighting circuit of the car. When the lamp bulb 28 is screwed into the socket 26, the filament islocated at the focal point a where it is most effective in producing a strong beam of light. p

It'is-a'pparent that the lamp bulb intercepts the position of the oil burner so that they cannot both be in the operative position at the same time. Whenthebulbfis in use the burner is removed and when the burner is in use the bulb is removed. The bulb is the regular lighting bulb of the car and is easily replaced. When these lamps are removed they are carried by the-bail 4C2 pivotally secured by lugs 41 -to-the housing and usually twoor I more lamps are zcarried in onehand so that the housing is tilted from' the vertical as V indicatedby line This brings-the lamp flame and the fumes therefrom towards the lamp socket 26- which is a fixtureof the housing. F-orthis reason the lamp socket is-placed on the line of' the flame v vhere the fumes pass over it when the housing'is tilted as described,or in rounding a curve on the track. This is an important feature ofthe invention, as "attempts to place the lamp socket in the head of the housing have not been satisfactory owing to the fumes from the burner alfecting the socket and its electrical connections. It will be observed that the large oil fount prevents the socket of the bulb being placed in the base of the housing.

- tour ofthe lens openings.

The upper part of the adapterjissomewhat triangular in shape and is secured to the housing bythree screws 31, 32 and 33, entering slotted holes as indicated at 36, Fig.

said lenses; an adapter for an electric light bulb comprising a. depending bracket opposite thewall of said housing between .a pair of saidl'enses andnot exceeding the width of said wall adjustably secured with aball engagement to said housing above the plane of said lenses and having a; horizontal socket adjacentthe wall of said housingbetween'the apertures for a pair of said lenses,

said-socket arranged to support a light bulb with its filament at the focal point of said lenses, said light bulb being I interchangeable with said oil burner for illuminating said 2. In a marker lamp as described, the combination, a housing having four lenses placed at right angles to each other and having a common focal :point, an adapter for securing an eleotric light bulb with its filament at the focal point of said lenses, said adapter comprising a bracket secured to said housing above the plane of said lenses by three screws spaced in the form of a triangle anda spherical projection integral with said bracket centered between said screws engaging the concave side of the curved wall of said housingand an extension on said bracket opposite the wall be tween a pair of said lensesand substantially the width of said wall supporting a horizontal socket with its centre on the same plane as the axis of said lenses for supporting said-bulb. p

In testimony whereof I afiix signature.

JOHN P. JOHNS.

5 which are covered by the washers 35. 'The spher1callpro1ect1on 34: is formed on 25 111 the centre of the triangle formed by the rests uponthecurved wall of the housing indicated in Fig. 4-. It will lbe observed from this figure that the bracket 25, is

screws 31,, 32 and 33 and this projection spaced from the housing 11, the. ball be- 7 ing the only'part engagingthe'f housing. It 7 is apparent thatby adjusting the screws 31,,

32 and 33, the bracket'25 will rotatenp'on the ballB l and therebya universal adjustment of 'theposition of the bulb filament 'inaybe obtained. I The slots 36 aid in securdjustment vertically.

his adapter. is "made has a unitary e011- sanction to ,be app1ied "to xistin marker Y lamps rising '0i1 I It is compara- 

